I like the idea of allowing users to put out bounties on other people's questions to help this out.  This may make things more worthwhile to research and answer.  A few caveats to this:

1) Multiple users can put out bounties on a question, however should anyone who has put out a bounty answer the question as well, they are prohibited themselves from collecting on the bounty, they can still answer the question though, and if they are marked as the answer the bounty points outstanding disappear to the eternal void.

2) Only the original person who asked a question can still mark an answer and award the combined bounty, no matter what.

3) A certain amount of reputation should be earned before you can put out a bounty on other people's questions (say 1,000 rep).  This will allow for a "master presence" effect drawing more experts to the question.